The present invention relates to a disk drive apparatus for recording and/or reproducing information on and/or from an optical disk such as an optical disk, magneto-optical disk, or the like.
For example, an optical pickup is known as a device for recording and/or reproducing information on and/or from an optical disk such as an optical disk, magneto-optical disk, or the like.
This kind of optical pickup includes an optical system having an objective lens for irradiating a laser beam on an optical disk, and a two-axis actuator for driving and shifting the objective lens in two directions, one being a direction parallel to the optical axis of the objective lens and the other being a direction perpendicular to the optical axis of the objective lens.
Further, a disk drive apparatus having an optical pickup comprises a feed mechanism for feeding the optical pickup in a direction parallel to the radial direction of an optical disk, a disk rotation drive mechanism for rotating the optical disk, and a support base for supporting the feed mechanism and the disk rotation mechanism.
The feed mechanism includes a slide base which supports the optical pickup, a main guide shaft and a sub guide shaft which support the slide base to be movable in the radial direction of the optical disk, and a drive mechanism which operates to feed the slide base. The slide base has a hold part which holds the pickup, and a support part supported to be movable by the main guide shaft and the sub guide shaft. The main guide shaft and the sub guide shaft are provided in parallel with the radial direction of the optical disk and also in parallel each other. These shafts are supported on the support base through a support member. The drive mechanism includes a rack member attached to the slide base, a group of gears for moving the rack member, and a feed motor for rotating and driving the group of gears. The rack member is engaged with a gear of the grouped gears. The disk rotation drive mechanism includes a disk table where an optical disk is mounted, and a spindle motor for rotating and driving the disk table. The support base is provided with an opening portion which enables movement of the optical pickup. The optical pickup is movably provided in the opening portion.
In the disk drive apparatus constructed as described above, the optical disk is rotated and driven by the disk rotation drive mechanism, so that the optical pickup is moved in the radial direction of the optical disk, thereby to perform recording and/or reproducing of information on and/or from a desired recording track of the optical disk.
Meanwhile, in a disk drive apparatus, a so-called skew occurs, i.e., the optical axis of the objective lens of the optical pickup is inclined with respect to the optical disk. In the disk drive apparatus, the state (hereinafter called a skew) of the optical pickup inclined relatively to the recording surface of the optical disk influences greater the recording/reproducing characteristics of information and results in a problem that assembling errors are often caused by the skew. Therefore, the disk drive apparatus must excellently adjust the skew.
A skew is caused by inclination of the axial directions of the main guide shaft and the sub guide shaft in the feed mechanism, or a warp of the disk table of the disk rotation drive mechanism, the rotation shaft of the spindle motor, or the support base.
In a conventional disk drive apparatus, the main guide shaft and the sub guide shaft are directly fixed on the support base or fixed thereto through a support member, so that their positions in the axial direction are fixed with respect to the support base. Therefore, there is a problem that it is difficult to adjust inclinations of the main guide shaft and the sub guide shaft with respect to the axial direction.
As a countermeasure for the skew, there can be a method in which assembly is carried out while mechanically adjusting the inclinations of the optical pickup and spindle motor which are set on the slide base of the feed mechanism, or a method in which recording and/or reproducing is performed excellently by detecting a skew and making electric control during recording and/or reproducing of an optical disk.
However, in the above-mentioned method of making adjustment during assembly, the optical pickup is assembled on the slide base while detecting an optimal value of a skew with the disk rotation drive mechanism driven to rotate. Therefore, there is a drawback that the production efficiency is remarkably lowered, and the equipment costs for an assembling device and the like are increased. Further, in this method of making adjustment during assembly, the optical pickup is difficult to detach and attach when making recovery of a malfunction or maintenance services. In the other method of electrically controlling the skew during recording and/or reproducing, the inclination of the optical pickup is constantly controlled by a motor or the like. Therefore, the number of components is increased, so that the manufacturing costs increase and high costs are required for control programs and the like.
The present invention hence has an object of providing a disk drive apparatus capable of easily and steadily adjusting a relative inclination of an optical pickup with respect to an optical disk.
To achieve the above object, a disk drive apparatus according to the present invention includes: a slide base having an optical pickup for recording and/or reproducing information on and/or from an optical disk; main and sub guide shafts provided in parallel with an radial direction of the optical disk, for supporting movably the slide base; a support base for supporting the main and sub guide shafts; and an adjust member having a bearing part provided such that a center of a shaft hole in an end of the main guide shaft and/or the sub guide shaft is inserted and supported is deviated from a center of an end surface substantially perpendicular to the axial direction of the main guide shaft and/or the sub guide shaft, and a plurality of contact surfaces, which form a substantially polygonal outer circumference and are brought into contact with the support base, thereby to adjust an inclination of the axial direction of the main guide shaft and/or the sub guide shaft.
Furthermore, a disk drive apparatus according to the present invention includes: a slide base having an optical pickup for recording and/or reproducing information on and/or from an optical disk; a guide shaft provided along a radial direction of the optical disk, for supporting movably the slide base; a support base for supporting the guide shafts; and an adjust member having a bearing part, an outer circumference formed in a substantially polygonal shape, and a plurality of contact surfaces to be brought into contact with the support base, thereby to adjust an inclination of an axial direction of the guide shaft, the bearing part being provided such that a center of a shaft hole in which an end of the guide shaft is inserted and supported is deviated from a center of an end surface substantially perpendicular to the axial direction of the guide shaft.
In the disk drive apparatus constructed as described above, the adjust member is rotated about the axis of the main or sub guide shaft, thereby to bring an arbitrary contact surface on the outer circumference into contact with the support base. As a result of this, the center of the shaft hole of the bearing part changes, because the center of the shaft hole of the bearing part is deviated from the center of the end surface. Therefore, inclinations of the axial directions of the main and sub guide shafts supported by the adjust member changes as the position of the shaft hole of the bearing part changes, in the disk drive apparatus. Thus, according to this disk drive apparatus, the inclination of the optical pickup relatively to the optical disk can be easily adjusted by rotating the adjust member about its axis.